我正在尝试在我的应用程序中使用自动完成功能。
搜索了一段时间后，我找到了以下教程：
http://www.claytical.com/blog/android-dynamic-autocompletion-using-google-places-api
有一个未解析的变量，称为s。创建 URL 的位置：
URLEncoder.encode(s.toString(), "UTF-8") +
我不明白这个变量是从哪里来的。
这里几乎是本教程中的整个代码都经过了一点修改。
public class PlacesListSearchActivity extends Activity {
private static final String TAG = "PlacesListActivity";
public ArrayAdapter<String> adapter;
public AutoCompleteTextView textView;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.places_search);
final ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,R.layout.item_list);
final AutoCompleteTextView textView = (AutoCompleteTextView)
findViewById(R.id.autoCompleteTextView1);
adapter.setNotifyOnChange(true);
textView.setAdapter(adapter);
textView.addTextChangedListener(new TextWatcher() {
public void onTextChanged(CharSequence s, int start, int before, int count) {
if (count%3 == 1) {
adapter.clear();
GetPlaces task = new GetPlaces();
//now pass the argument in the textview to the task
task.execute(textView.getText().toString());
}
}
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
// TODO Auto-generated method stub
}
public void afterTextChanged(Editable s) {
}
});
}
class GetPlaces extends AsyncTask<String, Void, ArrayList<String>> {
@Override
// three dots is java for an array of strings
protected ArrayList<String> doInBackground(String... args)
{
Log.d("gottaGo", "doInBackground");
ArrayList<String> predictionsArr = new ArrayList<String>();
try
{
//https://maps.googleapis.com/maps/api/place/autocomplete/json?input=Vict&types=geocode&language=fr&sensor=true&key=AddYourOwnKeyHere
URL googlePlaces = new URL(
"https://maps.googleapis.com/maps/api/place/autocomplete/json?input=" +
URLEncoder.encode(s.toString(), "UTF-8") +
"&types=geocode&language=en&sensor=true&key=" +
getResources().getString(R.string.googleAPIKey));
URLConnection tc = googlePlaces.openConnection();
BufferedReader in = new BufferedReader(new InputStreamReader(
tc.getInputStream()));
String line;
StringBuffer sb = new StringBuffer();
//take Google's legible JSON and turn it into one big string.
while ((line = in.readLine()) != null) {
sb.append(line);
}
//turn that string into a JSON object
JSONObject predictions = new JSONObject(sb.toString());
//now get the JSON array that's inside that object
JSONArray ja = new JSONArray(predictions.getString("predictions"));
for (int i = 0; i < ja.length(); i++) {
JSONObject jo = (JSONObject) ja.get(i);
//add each entry to our array
predictionsArr.add(jo.getString("description"));
}
} catch (IOException e)
{
Log.e("YourApp", "GetPlaces : doInBackground", e);
} catch (JSONException e)
{
Log.e("YourApp", "GetPlaces : doInBackground", e);
}
return predictionsArr;
}
//then our post
@Override
protected void onPostExecute(ArrayList<String> result){
Log.d("YourApp", "onPostExecute : " + result.size());
//update the adapter
adapter = new ArrayAdapter<String>(getBaseContext(), R.layout.item_list);
adapter.setNotifyOnChange(true);
//attach the adapter to textview
textView.setAdapter(adapter);
for (String string : result) {
Log.d("YourApp", "onPostExecute : result = " + string);
adapter.add(string);
adapter.notifyDataSetChanged();
}
Log.d("YourApp", "onPostExecute : autoCompleteAdapter" + adapter.getCount());
}
}
}
好的，我回答了我自己的问题。请看下面的答案！